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Physical layer simulations and analysis techniques were used to develop the error vector magnitude (EVM) metric specifying transmitter signal quality. These tools also proved to be very useful in specifying lower level hardware unit performance and predicting mobile user objective system (MUOS) satellite 8-PSK transmitter performance before the hardware was built. However, the verification of EVM...
Current DoD requirements call for a single enterprise terminal supporting up to 48/96 (threshold/objective) transmit and 56/112 (threshold/objective) receive communications carriers, not considering future expansion. The number of links supported by an enterprise terminal dictates aggregate servicing capacity. A single teleport/standardized tactical entry point (STEP) site can consist of five or more...
We present a complete scenario driven component based analytic model of 802.11 MAC and OLSR routing protocols in MANETs. We use this model to provide a systematic approach to study the network performance and cross-layer analysis and design of routing, scheduling, MAC and PHY layer protocols. The routing protocol is divided into multiple components. Componentization is a standard methodology for analysis...
One of the major QoS goals for future battlefield networks (FBN) is to ensure multi-level precedence and preemption (MLPP). Ensuring MLPP is difficult, partly due to the networking architecture for FBN which consists of wired ??red?? network connected by encrypted wireless ??black?? network. The security requirements for FBN do not allow passing information from black to red networks. So when congestion...
Integration of Commercial Off The Shelf (COTS) technology into MILSATCOM terminals may offer benefits over custom solutions. These include more affordable network nodes; reduction in development, acquisition, training, and sustainment expenditures; improved terminal interoperability; and, with modular integration, the ability to more easily incorporate future networking technology. This paper discusses...
This paper presents ViFiTM, a V-band wireless local area network (WLAN) that utilizes the unlicensed V-band spectrum while resolving the propagation challenges at V-band. ViFiTM allows for utilization of existing compatible waveforms, such 802.11g and ultra-wide band (UWB), and provides anti-shadowing capability to provide mobility throughout the network coverage area. In addition, three main applications...
Wireless sensor networks (WSNs) developed for the monitoring of critical military or civilian infrastructures are expected to have long life cycle with ultra-low power consumption. An ultra-low power wireless sensing scheme is developed by exploiting the unique features of infrastructure monitoring systems, which usually have long latency tolerance, low data rate, and strong correlation among data...
Efficient use of spectrum requires an accurate determination of interference effects. In this paper, we introduce a radio to radio (R2R) factor that quantifies the interference effects of one radio waveform on another based on multiple waveform properties instead of solely on intermediate frequency (IF) signal power. The R2R factor is formulated as a dimensionless correction term in the victims communication...
Traditional approaches for testing MANET protocols and applications prior to field experimentation often involve simulation tools or small-sized physical testbeds. However, simulation tools typically do not run in real-time and rely on simplified models rather than a real system, while physical testbeds are prohibitively expensive to build and operate. A more practical method is to use emulation tools...
Cognitive radio (CR) is a revolutionary wireless mobile communication technology. Smart users can use the CR technology to sense the surrounding environment, search for available spectrum resources and access spectrum dynamically. Differential frequency hopping (DFH) is known as an effective FH technique for increasing data rate of HF communication system. In this study, the cognitive radio technology...
Input to JTRS' future increment products may present an opportunity to address the design and the operational needs for MUOS handheld terminals. In terms of capacity, bit rate, coverage, availability and portability, MUOS handheld terminals provide significantly enhanced warfighter capability over the existing UHF satellite communication (SATCOM). In addition, it fulfills the needs for the hereto...
The Transmission Control Protocol (TCP) is ubiquitous, sophisticated, and effective. It also prevents the innovation needed to improve delivery of Internet services to the wireless tactical edge of DOD operations. We argue in this paper that TCP should be used as a short-range local access protocol for COTS compatibility rather than as the primary end-to-end transport protocol for the tactical GIG...
Emerging hybrid satellite communications and wireless network architectures support high bandwidth services and applications for tactical users. In this paper we propose a cross- layer design approach focusing on physical layer interaction on the application layer using an OPNET simulation environment. This paper studies the effect of fading on dynamic resource allocations and the impact of rain fading...
A key enabling functionality in implementing Cognitive Radio is to reliably detect the licensed users. In recent literature, cooperation among spectrum sensing terminals is suggested to offer reliable sensing performance. We consider the problem that the presence of malfunctioning or malicious sensing terminals will severely degrade the performance of cooperative spectrum sensing. In this paper, we...
A typical military airborne networking scenario involves small groups of relatively closely-spaced aircraft which fly as a unit to perform a common mission. These aircraft need to maintain very long data links with other aircraft in the presence of strong interference from hostile jammers. Due to the physical separation of the aircraft, the time difference of arrival can often be greater than the...
In network communication, Byzantine attacks, i.e., attacks in consequence of the packet dropping and cheating (modified packets), are usually difficult to guard against. Several multi-path packet routing schemes have been recently proposed to recover lost packets on account of the packet dropping (caused by path failures or attacks), but no effective solutions have been proposed to counter cheating...
In this paper we demonstrate an attack scenario in which Bluetooth enabled computers are remotely controlled by an attacker without any security software detecting the connection. We describe in detail the methods to deliver malware, evade detection, elevate permissions, and transport critical information out of the network via Bluetooth connections. A prototype system using state-of-the-art operating...
Active topology management in the future airborne networks (AN) can provide improved overall network throughput, efficiency, and scalability and is critical due to the high degree of platform dynamics involved. The RF links that form an airborne network must be established and reconfigured rapidly in response to aircraft joining and leaving the network, aircraft changing flight paths, and to changes...
This paper investigates the energy-bandwidth trade-off of various relaying strategies over the AWGN channel. The total energy consumption per information bit includes the receiver circuit processing energy at the relay and destination as well as the transmitted energy. With the cooperation of the source and relay, the end-to-end bandwidth efficiency can be improved at the cost of receiver processing...
In this paper, we present an automated region-of-interest-based video coding system for use in ultra-low-bandwidth applications. Region-of-interest (ROI) coding methodology specifies that targets or ROIs be coded at higher fidelity using a greater number of available bits, while the remainder of the scene or background is coded using fewer bits. This allows the target regions within the scene to be...
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